IXTRODUCTTON. 



17 



and maggots (which are without feet) from blow-flies, 

 house-flies, cheese-flies, &c., though this is not very rigidly 

 adhered to in common parlance. Maggots are also some- 

 times called worms, as in the instance of the meal-worm ; 

 but the common earth-worm is not a larva, nor is it by 

 modem naturalists ranked among insects. 



There are, however, certain lai-vse, as those of the Cicada, 

 the crickets, the water boatsman (Nofonedci), the cock- 

 roach, &c., which resemble the perfect insects in form, 

 excepting that they are destitute of wings ; but in the pupa 

 state these appear in a rudimentary condition, at least in 

 such species as have wings in the mature stage of existence. 



a, Ametabolous Pupa of Cicada; />, Caterpillar of tussock moth (Lariafascelina); c, 

 larva of the poplar beetle {Chrysomela popuU),; d, larva of Siiiex ; e, larva of the common 

 gnat. 



The pupa3 are active and eat. Insects, the larvae and pupae 

 of which are so similar to the adults, are termed Ametabolous 

 (a, without, j^ieraftoKy], change) ; those the larvse of which 

 undergo changes of a marked character, Metaholous (Insecta 

 ametabola and Insecta metabola, Burmeister). 



Larva3 are remarkably small at first, but grow rapidly. 

 The full-grown caterpillar of the goat moth (Cossus ligni- 

 perda) is thus seventy-two thousand times heavier than 



c 



